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DAVID P. WEBSTER, OF NEW YORK, Y.-

Letters Patent No. 76,679, dated April 14-, 1868.

IMPROVEMENT IN sMELTme LEAD oars.

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'ro WHOM IT MAY CONCERN;

Be it known that I, DAVID P. WEBSTER, of New York, in the county of NewYork, and State of New York, have invented certain new and-usefulImprovements in Smelting Lead Ores; and I hereby declare the followingto be a full, clear, and exact description of the same.

In Letter Patent ofthe United States granted to Alexander H. Everett, onthe 3d May, 1864, for improvement in smelting lead ores, is describedand claimed a process of smelting sulphuretted lead ores, which consistsin subjecting the ore, mingled with a certain proportion of refusescraps of tin plate, to a heating in a'reverberatory furnace, in themanner hereinafter described. I have found by careful experiments thatthis process is also-adapted to .the treatment of phosphurets andphosphates of lead, such as are found in the vicinity of Phoenixville,Pennsylvania; and my present invention consists in smelting or inreducing the lead from such J ores by the process referred to.

7 To enable those skilled in the art to understand and use my invention,I will now proceed to describe the manrier in which the same is or maybe carried into effect.

The furnace employed may be the ordinary reverbcratory for smeltinglead, and needs, therefore, no par ticular description. 1, In treatingphosphurets or phosphates .of lead by the process referred to, thefurnace is but heated to a red heat, and two hundred and fifty (250)pounds of scraps of tin plate are then spread evenly over the The doorsare next closed for a few minutes, until the scraps have attained abright red heat, after which they are again opened, and two thousand(2,000) pounds of phosphurcts orphosphatcs of lead, in a pulverizedstate,

are evenly spread over the heated tin-plate scraps. When this has beendone, the doors of the reverberatory are reclosed, and so remain untilthe ore has become heated to nearly a dull red heat, when they are againopened, and two hundred and fifty (250) pounds more of the tin-platescraps are carefully and evenly spread over the heated surface of theore. The doors are reclosed, and the whole mass is brought to abrightred heat, The doors are still kept closed for about fifteen minutes, andcare is exercised to keep the heat of the reverberatory at'a constanttemperature during this time. When the fifteen minutes have expired, thedoors are again opened, and the whole mass is raked and well stirred fortwo or three minutes, while care is'cxcreiscd to keep the mass at asuniform a thickness as practicable.

The stirring opcration should be repeated every fifteen minutes forabout two hours.

At the expiration of two hours the whole mass will have assumed thefluid state, when the whole of the lead will have been reduced. The tapat the side of the reverberatory is then drawn, and the lead is ready tobe cast into ingots.

I The furnace is next cleared of the slags, and the operation justdescribed repeated.

The advantages attending. the use oftin-pilatc scraps in this processhave been fully set forth in the patent above named, and need not berecited.

I have named definite proportions of tin-plate scraps and puosphurets orphosphates of lead. They have I been found in practice to yield the bestresults, but it is obvious that'the proportions may be varied, accordingto the natureof the ore to be treated. I do not, therefore, confinemyself to. any particular proportions, but

What I claim as my invention, and desire to secure by Letters Patent ofthe United States, is The improved process herein described for smeltingorreducing phosphurets or phosphates of load. In testimony whereof, Ihave signed my name to this specification before two subscribingwitnesses.

D. P. WEBSTER.

Wi tn ess es MARCELLUS BAILY, A. PoLLoK.

